At present, LED is widely used in illuminating devices, for instance, for forming an LED lamp, due to its high efficiency and high output flux. However, taking the driver to be matched with the LED lamp into consideration, there is a problem in thin and narrow spaces for the LED lamp having a big volume, that is, the space for installing a driver is quite limited in a thin and narrow LED lamp. Thus, the current LED lamps have a big volume as the cubic single driver installed therein has a big volume and are not conveniently mounted by customers in practical applications. In addition, in the current market, customers would like to simply mount the LED lamps just like mounting traditional lamps. That is to say, it is unwanted to have too much connection that complexes the structure of the LED lamp and too much carefulness for preventing problems such as safety problem in installation are not desirable.
However, in the existing technical solutions, as the space for a driver circuit is limited, said object is difficult to be achieved. Moreover, the current technical personnel have a technical prejudice, that is, the person skilled in the art, under the influence of the structure of traditional lamps, always would consider using a big single driver to drive all LEDs in series. But in order to realize the regular performances of the LED lamps, parts such as optical structure, heat sink and cover could hardly be manufactured to be smaller. Thus, in the existing solutions, the volume of a single driver driving the LED is always intended to be reduced, but as to a single inductor (or transformer) used for the single driver, it is really hard to be manufactured smaller as the frequency is impossible to be too high.
A solution currently used is a power supply having a high switching frequency, and a magnetic material having a high performance is employed to suppress EMC noises, but the effect is quite poor.
Besides, for a more efficient and smaller inductor and a simple circuit, there is no appropriate insulation structure, the layout on a single layer of MCPCB is difficult to be carried out, and it's impossible to arrange through holes in PCB.